Contaminated sinks: Sometimes the solution is part of the problem

January 12th, 2015

A hospital outbreak of Klebsiella oxytoca was linked to contaminated sinks which were used for both hand hygiene and disposal of patient body fluids, investigators reported.

K. oxytoca is primarily a health care–associated pathogen acquired from environmental sources. During October 2006–March 2011, a total of 66 patients in a hospital in Toronto, Ontario, Canada, acquired class A extended-spectrum β-lactamase–producing K. oxytoca with 1 of 2 related pulsed-field gel electrophoresis patterns. New cases continued to occur despite reinforcement of infection control practices, prevalence screening, and contact precautions for colonized/infected patients.

Cultures from hand washing sinks in the intensive care unit yielded K. oxytoca with identical pulsed-field gel electrophoresis patterns to cultures from the clinical cases. No infections occurred after implementation of sink cleaning 3×/day, sink drain modifications, and an antimicrobial stewardship program. In contrast, a cluster of 4 patients infected with K. oxytoca in a geographically distant medical ward without contaminated sinks was contained with implementation of active screening and contact precautions. Sinks should be considered potential reservoirs for clusters of infection caused by K. oxytoca.

“This outbreak also emphasizes the challenges associated with limited space and sinks in older hospitals,” the authors concluded. “Presumptively, these hand washing sinks became contaminated because they were used for the disposal of body fluids from colonized patients. While this is clearly unacceptable, nurses in the ICU are required to walk past several rooms (and out of isolation rooms) to reach the dirty utility room for disposal of body fluids, an activity that is also associated with risk. As we increasingly recognize the risks associated with hospital water and sinks, the design of ICUs becomes critical for protecting patients from these risks.”